This invention relates to a method and apparatus for checking and/or correcting alignment of a vehicle frame, body or various parts thereof.
Evaluating the alignment of vehicle frame and various associated parts can be rather complicated and time-consuming. A number of different systems are used with varying degrees of success. One approach utilizes one or more chassis gauges mounted on the chassis in centerline relation, each gauge including sighting pins to determine alignment. Such a system involves a painstaking approach if the preferred degree of accuracy is to be realized as, among other drawbacks, the gauges must be repositioned throughout the length of the chassis, thus requiring repeated recalibration.
Other approaches utilize laser beams aimed at targets suspended from the chassis. One such system involves the use of a complex and expensive frame structure extending along an end and side of a chassis slightly below the same and in spaced relation thereto. The corner of this L-shaped structure mounts a laser beam generator and beam splitter which directs a split beam to redirecting mirror units mounted on each leg of the structure. The mirror units in turn are slidable along each leg throughout the width and length of the chassis to permit a split beam to selectively and successively contact targets suspended from the chassis. Such a system is not only very expensive but also is quite time-consuming in operation.
Still another laser based system involves the use of two sweeping lasers which are spaced a predetermined distance from one another and which are mounted independently of a chassis at one end thereof and below the same to permit the sweeping of targets suspended from the chassis. This system relies on the principles of triangulation requiring dependence on a computer and special software. Not only does cost of the system hamper its use, but the fact that the user is totally dependent on a single software source is discouraging.